Screens are commonly used in the mining industry to separate the pellets of a mined granular product based on their respective particle sizes. To that end, each screen comprises a plurality of sieves having different meshes, and the product passes through the different sieves, from the sieve with the coarsest mesh to the sieve with the finest mesh. The largest pellets are then collected on the surface of the first sieve, and the finest are collected below the last sieve, for example using a hopper.
To favor the flow of the product between two successive sieves, the latter are generally stacked above one another.
To favor the passage of the pellets with the smallest particle sizes through the meshes of the sieves, each sieve is generally vibrated by an electrical vibrator, such as an unbalanced vibrator.
The existing screens are not, however, fully satisfactory. In fact, it is regularly necessary to operate on a sieve for maintenance of the screen. This operation is generally done by an operator, who to that end is required to enter the small vertical space separating two consecutive sieves. The operator must thus perform the maintenance while being confined in a narrow space where the air is most often saturated with fine particles. These operating conditions often cause work-related illnesses, in particular respiratory illnesses.